Abstract

IN VITRO EVALUATION OF THE ANTIBACTERIAL ACTIVITY OF SYZYGIUM AROMATICUM (CLOVE) OIL AND ITS INTERACTION WITH CIPROFLOXACIN AGAINST SOME GRAM NEGATIVE BACTERIA

Ogbuanya .C, Adonu, C.C,* Attama A.A, Okore V.C

dws

ABSTRACT

The plant Syzygium aromaticum is used by traditional healers for the treatment of various ailments. Recent scientific reports have confirmed some antimicrobial, anti-inflammatory and other therapeutic activities of the essential oil from this plant. The purpose of this study was to evaluate, in vitro, the antibacterial activity and the combined effects of essential oil from syzygium aromaticum (clove) and ciprofloxacin against some Gram negative bacteria(GNB). Hydro-distillation was employed in the extraction of essential oil from the dried flower buds of Syzygium aromaticum using the Clevenger apparatus. Preliminary antimicrobial Screening of the oil was carried out using agar-well diffusion techniques. The minimum inhibitory concentrations (MIC) of the oil and the ciprofloxacin were determined using agar dilution technique. Checkerboard agar dilution method was used to study the interactions of the oil and the ciprofloxacin. The respective mean MIC values of clove oil against Salmonella typhi, Escherichia coli, Klebsiella sp, Proteus mirabilis and Pseudomonas aeruginosa were 0.14 0.47%, 0.54 0.22 %, 0.31 0.53%, 0.69 0.18% and 0.73 0.10% whereas for ciprofloxacin, the respective MIC values in ug/ml were 0.16 0.66, 0.41 0.61, 0.49 0.77, 0.55 0.29 and 0.62 0.09. The combined effects of the two agents against Salm. typhi at ratios 90:10, 30:70, 20:80 and 10:90 were predominantly additive while the rest of the ratios produced indifference effects. Similarly, apart from a single antagonism produced against Kleb.spp at ratio 50:50 (ciprofloxacin: oil), the combined effects of the two agents against Kleb.spp at ratios 90:10, 80:20, 30:70, 20:80 and 10:90 were predominantly synergism while the rest of the ratios produced indifference effects. Further studies with these agents are recommended to investigate the possibility of combining the oil with ciprofloxacin to get a better therapeutic result.

Keywords: Syzygium aromaticum oil, Ciprofloxacin, MIC, Gram negative bacteria, Checkerboard.